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完整後設資料紀錄
DC 欄位 | 值 | 語言 |
---|---|---|
dc.contributor.advisor | 江宏仁(Hong-Ren Jiang) | |
dc.contributor.author | Yun-Hun Bai | en |
dc.contributor.author | 白耘翰 | zh_TW |
dc.date.accessioned | 2021-06-17T05:59:38Z | - |
dc.date.available | 2019-02-19 | |
dc.date.copyright | 2019-02-19 | |
dc.date.issued | 2018 | |
dc.date.submitted | 2019-02-13 | |
dc.identifier.citation | [1] Young, T., Philos. Trans. R. Soc, III. An essay on the cohesion of fluids. London, 1805, 95, 65
[2] Cassie ABD, Baxter S, Wettability of porous surfaces. Trans, 1944 Farad Soc 40: 546–551 [3] Eral, H.B., D.J.C.M. ’t Mannetje, and J.M. Oh, Contact angle hysteresis: a review of fundamentals and applications. Colloid and Polymer Science, 2012. 291(2): p. 247-260. [4] de Gennes, P.G., Wetting: statics and dynamics. Reviews of Modern Physics, 1985. 57(3): p. 827-863. [5] J. Lee, H. Moon, J. Fowler, C.-J. Kim, and T. Schoellhammer, Addressable micro liquid handling by electric control of surface tension, in Proc. IEEE Int. Conf. MEMS, Interlaken, Switzerland, Jan. 2001, p.499–502 [6] T. B. Jones, Dielectrowetting Driven Spreading of Droplets. Langmuir, 2002. 18, 4437 . [7] McHale, G., et al., Dielectrowetting driven spreading of droplets. Phys Rev Lett, 2011. 107(18): p. 186101. [8] Born F.R.S, M.A.X. and H.S. Green, A KINETIC THEORY OF LIQUIDS. Nature, 1947. 159: p. 251. [9] Sedev, R., The molecular-kinetic approach to wetting dynamics: Achievements and limitations. Adv Colloid Interface Sci, 2015. 222: p. 661-9. [10] Russell, A., E. Kreit, and J. Heikenfeld, Scaling dielectrowetting optical shutters to higher resolution: microfluidic and optical implications. Langmuir, 2014. 30(18): p. 5357-62. [11] Hage-Ali, S., et al. An EWOD driven millimeter-wave phase shifter using a movable ultrasoft metalized PDMS ground plane. in 2011 16th International Solid-State Sensors, Actuators and Microsystems Conference. 2011. [12] Jian, G., et al. Thermal switches based on coplanar EWOD for satellite thermal control. in 2008 IEEE 21st International Conference on Micro Electro Mechanical Systems. 2008. [13] Mugele, F. and J.-C. Baret, Electrowetting: from basics to applications. Journal of Physics: Condensed Matter, 2005. 17(28): p. R705-R774. [14] Parekh, D.P., et al., 3D printing of liquid metals as fugitive inks for fabrication of 3D microfluidic channels. Lab Chip, 2016. 16(10): p. 1812-20. [15] Shah, G.J., et al., EWOD-driven droplet microfluidic device integrated with optoelectronic tweezers as an automated platform for cellular isolation and analysis. Lab Chip, 2009. 9(12): p. 1732-9. [16] Pollack, M.G., R.B. Fair, and A.D. Shenderov, Electrowetting-based actuation of liquid droplets for microfluidic applications. Applied Physics Letters, 2000. 77(11): p. 1725-1726. [17] Sung Kwon, C., M. Hyejin, and K. Chang-Jin, Creating, transporting, cutting, and merging liquid droplets by electrowetting-based actuation for digital microfluidic circuits. Journal of Microelectromechanical Systems, 2003. 12(1): p. 70-80. [18] Gong, J. and C.J. Kim, All-electronic droplet generation on-chip with real-time feedback control for EWOD digital microfluidics. Lab Chip, 2008. 8(6): p. 898-906. [19] Geng, H., et al., Dielectrowetting manipulation for digital microfluidics: creating, transporting, splitting, and merging of droplets. Lab Chip, 2017. 17(6): p. 1060-1068. [20] Cottin-Bizonne, C., et al., Low-friction flows of liquid at nanopatterned interfaces. Nat Mater, 2003. 2(4): p. 237-40. [21] Mahadevan, L. and Y. Pomeau, Rolling droplets. Physics of Fluids, 1999. 11(9): p. 2449-2453. [22] D. Richard and D. Quere, Viscous drops rolling on a tilted non-wettable solid. Europhys. Lett., 1999, 48, 286–291 [23] Rossky, P.J., Exploring nanoscale hydrophobic hydration. Faraday Discussions, 2010. 146: p. 13. [24] Sun, C., et al., Control of water droplet motion by alteration of roughness gradient on silicon wafer by laser surface treatment. Thin Solid Films, 2008. 516(12): p. 4059-4063. [25] Nilsson, M.A. and J.P. Rothstein, Using sharp transitions in contact angle hysteresis to move, deflect, and sort droplets on a superhydrophobic surface. Physics of Fluids, 2012. 24(6): p. 062001. [26] Song, J.H., et al., A scaling model for electrowetting-on-dielectric microfluidic actuators. Microfluidics and Nanofluidics, 2008. 7(1): p. 75-89. [27] Nelson, W.C., P. Sen, and C.J. Kim, Dynamic contact angles and hysteresis under electrowetting-on-dielectric. Langmuir, 2011. 27(16): p. 10319-26. [28] Lu, Y., et al., Dynamics of droplet motion induced by Electrowetting. International Journal of Heat and Mass Transfer, 2017. 106: p. 920-931. | |
dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/71371 | - |
dc.description.abstract | 所謂的實驗室晶片(Lab-on-chip)為近幾年的研究主流,有許多使用電潤濕原理,來驅動數位式微流體的相關文獻,目前最新的設計是採用指叉狀電極陣列,以介電潤濕效應(Dielectrowetting)作為驅動力。此種類型的裝置在製造和操作上,皆享有優勢。但目前為止,我們尚未完全明瞭介電潤濕在驅動的過程中,影響液珠動態行為的各種因素。我們希望能對此有更佳深入的了解。本篇論文主要探討使用指叉狀電極設計的數位式微流體制動器,在驅動液珠的過程中,影響液珠動態行為的種種因素。
首先我們製作出一具有超疏水表面之介電潤濕裝置,用該裝置量測了水珠(DI Water)在靜態之下接觸角。也在施加交流電場的情況下,找出了電壓與接觸角之間的關係,以及水珠受電場影響後達到平衡態所需的反應時間。接著讓水珠在以不同傾斜角度在裝置表面滾落,過程中經過和中軸夾45度角之電極,和未施加電壓的情況相比,其路徑會產生橫向偏折,偏折量和電壓大小呈正相關。在我們分析了偏折量與電壓間的關係和橫向作用力,發現水珠在離開電極的當下偏折最為明顯,且不能只用介面間接觸角差異來解釋,還有其他因素的影響。 我們更進一步,重新設計電極,讓水珠通過與中軸呈0度及90度夾角之電極,觀察到兩者之間運動情形,有明顯差異。分析結果發現在介電潤濕效應中,方向性的親疏水,對水珠動態行為有很大的影響。 我們最後在介電潤濕裝置上方2mm處增加一片平板,將水珠固定於此。接著等速移動下方的電極,比較不同速度、不同電壓下水珠的動態接觸角,並且用分子動力理論(MKT)進行分析。結果發現在水珠行徑方向與電場平行時,若是將介電泳力等校於毛細力來建立模型,可以有效描述動態接觸角受電場的影響,但當行徑方向與電極垂直時,還沒辦法精準的使用模型分析。 | zh_TW |
dc.description.abstract | Lab-on-chip has been a popular research topic in recent years. The latest actuator is driving droplets on interdigitated electrodes using the mechanism so called “dielectrowetting”. This kind of device only require a single plate of electrodes.
This system does not require the top plate (cover), allowing for the handling of a much wider range of liquid volumes with easily accessible and simplified structures. Bus so far, we don’t fully understand the dynamics behavior of droplets during actuating process. This paper is focus on the dynamics behavior of droplets in digital microfluidic actuator driven by dielectrowetting. In this experiment, we represented a dielectrowetting device with super-hydrophobic treatment and placed a drop of DI water (30μl) on its surface. We measured the advancing angle, receding angle, contact angle hysteresis and critical sliding angle of droplet under stationary condition. By applying an external electric field (AC), we observed how the magnitude of voltage influences the contact angle and the reaction time for droplet to get to new equilibrium state. After that, we let droplets roll freely down on the surface of dielectrowetting device which was inclined at a certain angle. Its path was deflected due to the dielectrowetting effect created by electrodes which placed on the surface with 45 degree of included angle. We measured the lateral displacement of droplet and it has positive correlation with magnitude of voltage. Results also showed that the force which caused droplet to deflect mainly happened on the edge of electrode and it can’t be contributed to difference of contact angle between two surfaces. Hence, we redesigned the alignment of electrodes, now with parallel and vertical to the path of droplet. The behaviors of droplet were significantly different when passing through two kind of electrode that mentioned above. Proofing that the phenomenon of directional wettability in dielectrowetting has huge impact on dynamics of droplet. In order to obtain more accurate data on dynamics contact angle, we fixed the droplet on a hydrophilic upper surface. By moving the electrodes on lower plate with constant velocity, we have measured the dynamics contact angle under different applied voltage. Finally, we used molecular kinetic theory to analyze dynamics contact angle. We discovered that our model is suitable to describe the dynamics angle change due to the influence of dielectrowetting, but only comply when applied electric field is parallel to the path of droplet. Further research is needed when applied electric field is vertial to the path of droplet. | en |
dc.description.provenance | Made available in DSpace on 2021-06-17T05:59:38Z (GMT). No. of bitstreams: 1 ntu-107-R04543042-1.pdf: 8004172 bytes, checksum: 5921227fd2f3f380da3ffc3704c6bfa3 (MD5) Previous issue date: 2018 | en |
dc.description.tableofcontents | 目錄
一、 導論 1.1 前言 1 1.2 背景理論 2 1.2.1 Surface Tension表面張力 2 1.2.2 Young’s Equation 楊氏方程式 3 1.2.3 Cassie-Baxter 疏水模型 4 1.2.4 Contact Angle hysteresis, CAH 接觸角遲滯 6 1.2.5 Electrowetting 電潤濕 8 1.2.6 Liquid Dielectrophoresis, L-DEP 流體介電泳 10 1.2.7 Dielectrowetting 介電潤濕 12 1.2.8 Molecular Kinetic Theory (MKT) of Dynamic Wetting 動態潤濕下的分子動力模型 16 1.3 文獻回顧 17 1.3.1 使用EWOD之原理的微流體制動系統 17 1.3.2 使用L-DEP之原理的微流體制動系統 20 1.3.3 動態下液珠之動態接觸角與表面受力之分析 24 1.4 實驗動機 33 二、 實驗器材及樣本製作 2.1 ITO導電玻璃 34 2.2 雷射打標機 35 2.3 Tetraethyl orthosilicate四乙氧基矽烷 36 2.4 Teflon水溶液 36 2.5 DI Water去離子水 37 2.6 加熱裝置 37 2.7 電壓輸出裝置 38 2.8 控制軟體、信號輸出介面及硬體 39 2.9 實驗記錄裝置 39 2.10 液珠接觸角量測 39 2.11 影像分析軟體 40 2.12實驗樣本製作流程 42 2.13 電極製作 42 2.14 絕緣層 43 2.15 超疏水層 43 三、 靜態分析 3.1 水珠靜態接觸量測、受力分析 45 3.2 水珠接觸角與外加電壓之關係 47 3.3 接觸角變化之反應時間與電壓之關係 49 3.4 小結 50 四、 水珠路徑偏折實驗 4.1 實驗架設 51 4.1.1 傾斜平台 52 4.1.2 使水珠偏折之介電濕潤裝置設計 52 4.1.3 針筒式泵浦 54 4.1.4 電極開關控制 55 4.1.5 軟體驅動介面 56 4.2 實驗參數 57 4.2.1 施加電壓與操作頻率 58 4.2.2 平台傾斜角度與水珠滾落速度 58 4.3 水珠偏折之實驗結果 59 4.4 水珠偏折橫向速度分析 63 4.5 小結 66 五、 水珠動態及受力分析實驗 5.1 實驗架設 68 5.1.1 電極設計 68 5.1.2 四組電極之開關 68 5.2 實驗參數 70 5.3 水珠滾落速度之實驗結果 70 5.4 水珠運動模式分析 75 5.5 水珠動摩擦力之受力分析 78 5.6 水珠在不同速度下之受力分析 80 5.7 水珠在不同階段之接觸角 83 5.8 小結 86 六、 單軸平台上之動態接觸角量測實驗 6.1 實驗架設 88 6.2 實驗參數 89 6.3 不同速度下之動態接觸角量及CAH 90 6.4 不同電壓下之動態接觸角量及CAH 91 6.5 小結 96 七、 理論分析及模型建立 7.1 動態接觸角理論模型建立與分析 97 7.2 水珠動態接觸角在電極中受介電潤濕影響之模型建立 100 7.3 水珠於電極中受介電潤濕影響之數據分析 103 7.4 水珠動態接觸角在交界面受介電潤濕影響之模型建立 107 7.5 水珠動態接觸角在交界面受介電潤濕影響之數據分析 109 八、 總結與未來展望 111 九、參考文獻 112 | |
dc.language.iso | zh-TW | |
dc.title | 液珠受介電潤濕影響於超疏水表面之動態分析 | zh_TW |
dc.title | Dynamics analysis of droplets on super-hydrophobic surface under influence of dielectrowetting effect | en |
dc.type | Thesis | |
dc.date.schoolyear | 107-1 | |
dc.description.degree | 碩士 | |
dc.contributor.oralexamcommittee | 李雨(U Lei),王安邦(An-Bang Wang) | |
dc.subject.keyword | 指叉狀電極,介電潤濕,超疏水,動態接觸角,接觸角遲滯, | zh_TW |
dc.subject.keyword | Interdigitated electrodes,Dielectrowetting,Super-hydrophobic surface,Dynamics Contact Angle,Contact Angle Hysteresis, | en |
dc.relation.page | 113 | |
dc.identifier.doi | 10.6342/NTU201900500 | |
dc.rights.note | 有償授權 | |
dc.date.accepted | 2019-02-13 | |
dc.contributor.author-college | 工學院 | zh_TW |
dc.contributor.author-dept | 應用力學研究所 | zh_TW |
顯示於系所單位: | 應用力學研究所 |
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